Drill.



W. H. BLOSS.

DRILL.

APPLICATION FILED SEPT.14. 1914.

Patented Nov. 30, 1915.

V" INVENTOH 2] Mfl bm 6. 5/056.

ATTORNEY UNITED STATES PATNT @FFIQE. 7

WILLIAM H. BLOSS, OF INDIANAPOLIS, INDIANA, ASSIGNOR OF ONE-HALF 'IO WILLIAM D. IIAMER, OF INDIANAPOLIS, INDIANA.

DRILL.

Specification of Letters Patent. t t NO 30, 9 5

Application filed September 14, 1914. Serial No. 881,702.

To all whom it may concern:

In the first two figures there is shown 2.

Be it known that 1, WILLIAM H. BLoss, a flarge piece of metal 10 to which a thin citizen of the Jnited States, and a resident of Indianapolis, county of Marion, and State of Indiana, have invented a certain new and useful Drill; and I do hereby declare that the following is a full, clear, and exact description thereof, reference being had to the accompanying drawings, in which like letters refer to like parts.

The object of this invention is to drill by. one operation of one tool an inwardly spreading hole in metal or other material. Such a hole is peculiarly well adapted for the insertion of rivets or for securingone piece of metal to another which is so large that it is impractical or undesirable to in sert a bolt through it. Heretofore such holes have been made by boring a plain hole and then removing the boring tool and inserting a reamer to ream out the inner portion of the hole and thus enlarge it.

The chief feature of the invention consists in combining with a tubular casing, a stock longitudinally movable therein with the end of which a pair of cutters are connected so that they will be oscillated, said cutters being controlled by the casing. At the beginning the casing engages the cutters for substantially their length and holds them so that they drill at the beginning a substantially straight hole. I As the tool stock is not along the casing, the cutters will gradually protrude beyond the ends of the casing and spread as they protrude and, therefore, make an undercut hole. versing the movement of the tool stock, the cutters can be removed from the hole.

The full nature of the invention will be understood from the accompanying draw ings and the following description and claims.

In the drawings, Figure 1 is a section through two pieces of metal riveted together by a rivet in a hole made by this machine. Fig. 2 is a section on the line 2-2 of Fig. 1. Fig. 3 is a central longitudinal section of a portion of the hole forming tool with the parts in idle position. Fig. 4 is the same with the parts in position after the hole has been partly formed. Fig. 5 is the same with the parts in position when the hole has been entirely formed. Fig. 6 is a section on the line 66 of Fig. 1. Fig. 7 is a section on the line 77 of Fig. 4.

By reiece of metal 11 is secured by a rivet 12. n the first place a hole 13 must be formed iin the metal 10 which is substantially bellnape or inwardly flaring and then the rivet 1nserted with its inner end red hot so that it spreads and fills the cavity of the 1 hole. This is an effective means for securing piece of metal to a very large piece of metal. through which it is not desired to jeXtend a bolt. it is often impossible to employ bolts and in such cases rivets can be secured as above explained.

The invention relates to means for forming the rivet hole or cavity 13. As shown herein it consists of a tubular casing 15 in which there is a tool stock 16 longitudinally movable by means not shown. At its ends said tool stock has a cylindrical recess 17. There is also a spiral passage 18 on the inner wall of the casing for the escape of metal shavings.

There is a pair of cutters 20, each of which is substantially semi-cylindrical in cross section so that the two together fill the cavity of the casing 15. The inner ends of the cutters have cylindrical heads 21 on them adapted to fit in the circular recesses 17 of the tool stock so that said cutters 20' can rock and permit their outer ends to spread apart as they protrude more and more from the end of the casing. The cutting ends of the cutters 20 have reversely curved cutting edges 22 along their inner and adjacent surfaces. They also have longitudinal beveled surfaces 23 along the edges of the adjacent surfaces of the cutters.

The device is operated as follows: The tool stock is in the position shown in Fig. 3. The end of the casing is applied to the metal in which the hole or cavity is to be bored and then the tool stock and cutters are rotated and as they are rotated, they are gradually fed toward the metal in which the hole or cavity is being formed. As the cutting ends of the cutters protrude from the casing, they begin to cut and bore the metal. The inner cutting edges are beveled from the extreme lateral point to one side inward to a point at the opposite side of the cutter and said cutting edges 2:2 are in the tool cutters reversely arranged, the ends of the cutters bent to spread as they enter the metal. This tendency to spread is resisted by the end of the casing 15, but as the cutters protrude more and more from the inner casing, they have a common axial line, the cutting ends of the cutters spreading and as they do so they simultaneously bore the hole inward and enlarge it. This is continued until the hole or cavity is completely formed. At the .Fig. 1.

The invention is not limited to any particular form of the cutters or the manner of mounting them in connection with the tool stock, as these features may be varied to suit the Work of the tool. The metal shavings Will pass out through a passage 18 in the casing. Therefore, with this mechanism, an undercut hole is simultaneously bored in- Ward and enlarged or undercut and by a single tool.

The invention claimed is:

1. Means for boring an undercut holeincluding a casing, and rotatable boring means mounted and movable therein and having a plurality of cutters adapted to spread from each other as they issue from the casing While boring for simultaneously boring inward to form the depth of the hole and boring angularly to undercut the hole.

2. Means for boring an undercut hole including a casing, and rotatable boring means mounted in said casing having a plurality of cutters curved away from each other on their inner edges so as to spread as they are forced outward from-the casing.

3. Means for boring an undercut hole including a tubular casing, a tool stock mounted therein so as to have both lateral and longitudinal movement, and a pair of similarly formed and oppositely located cutters mounted in connection with the end of said tool stock so as to be oscillatory in parallel planes, the inner edges of said cutters being oppositely beveled so that they will tend to spread as the hole is being bored and such spreading movement will be resisted and controlled by the end of the casing as the cutters graduallv protrude therefrom.

a. Means for boring an undercut hole including a tubular casing, a tool stock located and longitudinally movable therein having a transverse cylindrical recess in the end thereof, and a pair of cutters with cylindrical heads fitting in said recess so that the two cutters will rock in parallel planes, the inner edges of the cutters being oppositely beveled along with the adjacent edges and the outer edges of the cutters adapted to engage the end of the casing, whereby the end of the casing controls the spreading movement of the cutters.

5. Means for boring an undercut hole including a tubular casing, a tool stock located and longitudinally movable therein having a transverse cylindrical recess in the end thereof, and a pair of cutters with cylindrical heads fitting in said recess so that the two cutters will rock in parallel planes and said cutters being semi-cylindrical in cross section,'the inner edges of the cutters being oppositely beveled along the adjacent edges and the outer edges of the cutters being adapted to engage the end of the casing, whereby the end of the casing controls the spreading movement of the cutters.

In witness whereof, I have hereunto aiiixed nr'y signature in the presence of the witnesses herein named.

WILLIAM H. BLOSS. Witnesses J. H. WnLLs, R. G. Looirwoon.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents.

Washington, D. C. 

